This relates generally to electronic devices and, more particularly, to electronic devices with light-emitting diode arrays.
Electronic devices often include light-emitting diodes. For example, cellular telephones, computers, and televisions have displays that are backlit using light-emitting diodes. A typical backlight includes light-emitting diodes that launch light into the edge of a rectangular light guide plate. Scattered light from the light guide plate serves as backlight for the display.
It can be challenging to provide sufficient backlight illumination in a display. For example, in large displays, backlight requirements scale with increasing area, whereas the space available for light-emitting diodes along the edges of a light guide plate tends to scale only with the edge length of the light guide plate. There may therefore be a need to closely space light-emitting diodes, leading to heat buildup during operation.
Light-emitting diode lifetimes can be significantly affected by changes in operating temperature. High temperatures can degrade performance rapidly. For example, an operating temperature increase of 20° C. may reduce light-emitting diode lifetime by a factor of two or more.
It would therefore be desirable to be able to provide an electronic device with improved light-emitting diode heat sinking capabilities.